Environment bioremediation from toxic aldehydes using a versatile Aldehyde Dehydrogenase endowed with broad substrate specificity

Aldehydes are a large class of electrophilic carbonyl compounds present in large amount within the environment to which mammalian are pervasively exposed. Despite a significant health risk due to exposure, the mechanism of aldehyde toxicity is still poorly understood and the toxic mechanisms are only revealed in general terms because the toxic aldehydes are structurally different and have diverse biological targets. Aldehydes present in the environment are derived from both natural and anthropogenic sources and the possibility of exposure occurs outdoors and indoors, including the workplace. Indeed, these compounds are also present in foods, non-alcoholic beverages, cosmetics, and hand sanitizers. Also, lifestyle choices such as tobacco cigarettes, e-cigarettes, and alcohol expose people to aldehydes. Different aldehydes present in the environment are considered human carcinogens that irritates the upper respiratory tract when inhaled. In particular, acetaldehyde and formaldehyde are classified as Group 1 carcinogens by the International Agency for Research on Cancer (IARC). In general, pollutants’ stability, low solubility, and resistance to physical, chemical, and biological degradation pathways are the main reasons for their toxicity. In the recent years, enzymes are increasingly emerging as the most efficient bioremediation tools, thank to their capacity to progress all chemical changes on pollutants. Indeed, their specificity is usually broad enough to act on different molecules with similar structures. At the forefront of protection from environmental sources of reactive aldehydes is public awareness. Unless knowledge is properly disseminated, individuals will neither be cognizant of the risks associated with reactive aldehydes exposure nor capable of taking the necessary steps to minimize exposure. Precautionary measures and lifestyle modifications to reduce reactive aldehyde exposure should be a focus of public health, to ultimately reduce the potential risk for developing cancer or cardiovascular diseases. In parallel, the scientific community should make available useful strategies for decontaminating the environment from toxic aldehydes. In this context, the goal of our research project is to create a novel aldehyde dehydrogenase able to oxidize many, if not all, toxic aldehydes that are distributed in different environmental settings. To do this, we rely on a multidisciplinary approach in which both the biochemical and the chemical activities will be constantly complemented by in silico investigations. Our goal is to provide the community with an effective and highly specific tool that can be used in a versatile and efficient manner in the various situations of environmental contamination by toxic aldehydes.